Embedded Internet for Pulse Oximeters

In recent years there has been many investigations into sleeping disorders. Many studies are carried out in specially equipped units in which a patient is monitored whilst sleeping. Measurements that are taken are in the form of ECG, EMG, EEG, nasal airflow, and abdominal movement.

Pulse oximetry data is also recorded during the night. Pulse oximetry is the measurement of pulse rate and oxygen saturation of blood. Along with other measurements pulse oximetry data is used in the diagnosis of sleeping disorders. Recent studies have shown that diagnosis of sleeping disorders is better suited to a location of familiarity rather than a hospital situation. Amongst others, this is one of the many reasons that remote monitoring of medical equipment, such as the pulse oximeter, is a forward step in sleep medicine.

In building an “embedded internet for pulse oximeters” a door is opened on the possibility of remote monitoring via the Internet. This solution needs to be inexpensive relative to the cost of a pulse oximeter and the system needs to be robust as it will be portable. Ease of use is yet another major factor when designing such a system. Simplifying the operation of the device allows for less technical operators to adequately use the equipment to full potential.

The proposed system named Oximeter Internet Interface or oi^2, is a web server connected via RS-232 serial interface to a pulse oximeter. The oxinet is able to serve pulse and SpO2 data as well as trend information to the Internet. The medical staff can download trend data and view real time streaming data from any web browser. This is accomplished through the language of the Internet, HTML and java applets.

The design of an Internet based solution can be broken down into two major components, these being the server side and the client side. The server side includes the control and data acquisition from the pulse oximeter and serving this information up to the Internet. The client side includes the retrieval of information from the Internet and displaying that information in a human readable form.

An Internet solution such as this is not a comprehensive finished product but more of a stepping-stone to a fully functional system. The oxinet has been demonstrated at the Mater Children’s Hospital as a proof of concept. The idea was widely supported by staff and this led to more in depth analysis of the feasibility of such a device. It can be concluded that this proof of concept can be extended to a commercially viable product.
Author: Matthew Roy Burey
Source: The University of Queensland